31012420 has 48 divisors (see below), whose sum is σ = 70298928. Its totient is φ = 11448320.

The previous prime is 31012411. The next prime is 31012439. The reversal of 31012420 is 2421013.

It can be written as a sum of positive squares in 8 ways, for example, as 2985984 + 28026436 = 1728^2 + 5294^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 31012420.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17160 + ... + 18880.

It is an arithmetic number, because the mean of its divisors is an integer number (1464561).

Almost surely, 2^31012420 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31012420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35149464).

31012420 is an abundant number, since it is smaller than the sum of its proper divisors (39286508).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31012420 is a wasteful number, since it uses less digits than its factorization.

31012420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1800 (or 1798 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 31012420 is about 5568.8796000632. The cubic root of 31012420 is about 314.1800122696.

Adding to 31012420 its reverse (2421013), we get a palindrome (33433433).

The spelling of 31012420 in words is "thirty-one million, twelve thousand, four hundred twenty".